Pros
It's a fun atmosphere and extremely fast-paced. You have to be able to adapt well and handle high stress situations. Shipments come in every day, the floor layout is always changing, and you need to be able to keep up. Most everyone I work with are a lot of fun and make going to work much easier. If you're lazy, not a hard worker, and don't adapt well to change, this is not the place for you. But if you love always having something to do, don't mind working until late hours of the night (especially if you work at a large xxi location), then you should be good fit for the job.
Cons
The hours can be long and grueling. You have to stand for long hours and when running around the store doing go-backs can get pretty exhausting. The # 1 complaint I get while working is the "exchange" policy. Customers only have 21 days to return their merchandise but the tags have to be attached, they must have their receipt, and you can only receive store credit or do an exchange. However, sometimes a manager will make an exception and this can be very frustrating for both the employees and the customers. It's important for the cashiers to explain the exchange policy to every customer that is not familiar with it. Also, a lot of nights employees will be there until 2-3am. This is mainly during the holidays and I also need to take into account that I work at a larger version of the normal Forever 21 store.